WASHINGTON, Oct 11 (Reuters) - As many as 14,000 people - more than previously thought - received possibly tainted steroid injections tied to a deadly U.S. meningitis outbreak and patients should watch for symptoms for several months, health officials said on Thursday.

The officials said the company at the center of the outbreak, the Massachusetts New England Compounding Center, appeared to have violated its license by producing large quantities of drugs rather than prescriptions for individual patients, as calls grew for a criminal probe.

"This organization chose to apparently violate the licensing requirements under which they were allowed to operate," said Dr. Madeleine Biondolillo, director of the Massachusetts Department of Public Health's Bureau of Health Care Safety and Quality.

NECC officials were not immediately available for comment.

Biondolillo was joined by officials from the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration in a briefing on the outbreak. The CDC said the number of people at risk, which is 1,000 higher than earlier estimated, was revised after consulting with health authorities.

Fourteen patients have died from the rare form of fungal meningitis and 169 people have been infected, a rise of 32 cases since Wednesday, the CDC said. One more patient had an infection after an injection in the ankle, but meningitis has not yet been confirmed.

Infections have been detected within two weeks of a patient receiving the medication, on average, and up to 42 days afterward.

But anyone exposed to the NECC-supplied vials of the steroid methylprednisolone acetate - used to treat back pain and other conditions - should be vigilant for health problems for several months, CDC officials said. Local health authorities have contacted over 90 percent of patients who may have been exposed.

Florida reported a second death from meningitis and Indiana reported its first death from the outbreak, with cases confirmed in 11 states.

Richard Blumenthal, who sits on the Senate's Health Oversight Committee, said on Thursday he requested a federal criminal probe in a letter to U.S. Attorney General Eric Holder.

"I've reached no conclusions, but there are at least sufficient facts to warrant an investigation," Blumenthal, a former Connecticut state attorney general and federal prosecutor, told Reuters in a telephone interview.

"The company, its officers, employees and maybe others may have violated state and federal criminal laws in their potential misrepresentations to government agencies regarding their products," he said.

MAJOR HEALTH SCANDAL

Meningitis is an infection of the membranes covering the brain and spinal cord. Symptoms include headache, fever and nausea. Fungal meningitis, unlike viral and bacterial meningitis, is not contagious.

The outbreak has developed into a major health scandal, with authorities scrambling to determine how the steroid treatments were contaminated, track down those affected and treat them. It has also raised questions about how the pharmaceuticals industry operates and is regulated.

"We're continuing to investigate the facts and make sure we have a thorough understanding of exactly what is happening and exactly what we were or were not told," said Deborah Autor, FDA deputy commissioner for global regulatory operations and policy.

"The world has changed a lot from the days of mortar and pestle," Autor said. "This is the time for pharmacists, for lawmakers, for regulators, for doctors, to grapple with this new model of pharmacy compounding and come up with a regulatory scheme that appropriately controls risk."

The FDA regulates drug manufacturers but not the practice of compounding, in which pharmacies prepare specific doses of approved medications, based on guidance from a doctor, to meet an individual patients' need.

The agency can investigate a pharmacy once a risk to public health arises, and is now part of a probe of NECC, which operated out of a brick complex next to a waste and recycling operation in a western suburb of Boston. The company has suspended operations and recalled all of its products.

The FDA said on Thursday that more than 50 vials of steroid treatments from NECC t ested positive for a fungus that causes meningitis.

The pharmacies are owned by Gregory Conigliaro, an engineer, and his brother-in-law Barry Cadden, a pharmacist who was in charge of pharmacy operations at NECC. The waste and recycling facility is another of Conigliaro's business interests.

"It does seem like the agencies, both at the state and the federal level, may have been misled by some of the information we were given," Massachusetts Governor Deval Patrick told reporters on Wednesday.

In six states - Tennessee, Michigan, Maryland, Virginia, Florida and now Indiana - the outbreak has claimed lives.

Five new cases were reported in Tennessee, which remained the hardest-hit state with 49 cases, the CDC said. Michigan added 11 cases and was at 39 on Thursday, with Virginia adding three to reach 30 and Indiana six to reach 21, the CDC said.

The other states reporting cases are Maryland (13), Florida (7), Ohio (3), Minnesota (3), New Jersey (2), North Carolina (2) and Idaho (1), the CDC said.